1. Field of the Invention
The present invention relates to an optical disk, an optical recording/reproducing apparatus and a method thereof. More particularly, the present invention relates to an optical recording/reproducing apparatus and a method for tuning a write strategy using an optical disk having divided write strategy tuning areas.
2. Description of the Related Art
As computers are widely utilized, various peripherals and components for effectively utilizing the computers, are increasingly being developed. Developments, such as various auxiliary storage media for storing saved programs or materials when a power supply is stopped, are becoming popular. General auxiliary storage media are classified as a magnetic storage medium and an optical disk storage medium. Recently, the optical disk medium has advantages over the magnetic storage medium because the optical disk medium has a high-storage capacity and high-speed searching capability.
An optical disk includes a recording medium that optically writes and reproduces data. The optical disk is classified into a compact disk-ROM (CD-ROM) and a digital versatile disk-ROM (DVD-ROM) that are read-only optical disks; a CD-Recordable (CD-R) and a DVD-R that are recordable one time only; and a CD-rewritable (DC-RW) and a DVD-RW that are repeatedly recordable.
An optical recording/reproducing apparatus scans a predetermined track of such an optical disk with optical signals, that is, laser beams, and thereby creates a land and groove on the optical disk. The optical recording/reproducing apparatus writes data of 0 or 1 to the land and groove and reproduces data by detecting a reflection light obtained by scanning the optical disk with optical signals or laser beams.
The optical disk has a different medium characteristic and thickness depending on the optical disk type. Similar type optical disks are also different from one another in characteristics depending on a manufacturer. There are about 60 types of DVD-R, 20 types of DVD-RW, and 10 types of DVD-RAM. Accordingly, if the optical recording/reproducing apparatus records data to various types of optical disk according to a fixed write strategy, incorrect data would be likely written to the optical disk. The write strategy determines how the optical disk is scanned with the optical signals. More specifically, the write strategy determines a power level and scanning time of the optical signal. The write strategy is determined based on an amplitude and duty of a driving pulse signal supplied from a laser diode for scanning with optical signals. The power level of an optical signal becomes greater as the amplitude of the driving pulse signal increases. Thus, the scanning time becomes prolonged as the duty increases.
The optical recording/reproducing apparatus uses a different write strategy depending on the types of optical disks in order to achieve a normal data recording operation. For this, a conventional optical recording/reproducing apparatus stores the write strategies suitable to various types of optical disk in a firmware. When an optical disk is placed on the optical recording/reproducing apparatus, the type of optical disk is determined. Information about the write strategy corresponding to the determined type of optical disk is read out from the firmware so that data is recorded according to the write strategy. Meanwhile, data may be recorded in a predetermined default write strategy if an optical disk does not have write strategy stored in the firmware. The default write strategy is a value that is arbitrarily set to cover various types of optical disks.
The write strategy stored in the firmware is set differently at the time of manufacture depending on the types of optical disk. Therefore, a problem exists because the write strategy shows a different function depending on the types of mass-produced optical recording apparatus. Accordingly, a selected write strategy requiring tuning within a predetermined range to be suitable to the optical recording/reproducing apparatus. The optical disk has a test area in a predetermined region to tune the write strategy. For example, the test areas include a power calibration area (PCA) in the DVD-R and DVD-RW and a drive test zone (DTZ) in the DVD-RAM.
Since the conventional optical recording/reproducing apparatus uses the test area of the optical disk to not only tune the write strategy, but to also record data, the test area is very rapidly consumed.
Meanwhile, a power calibration of an optical signal has to be performed in a non-recording area. Accordingly, if the entire test area is consumed, a clear operation is required to erase data from the test area in order to perform the power calibration of the optical signal. However, in spite of the clear operation, there still remains damage on a surface of the test area due to the previous data recording operation. Therefore, it is impossible to accurately detect an optimal power level and an optimal scanning time.
Tuning of the scanning time often requires overwriting data depending on whether a user overwrites data to a recording area. More specifically, when a user overwrites data to the optical disk, the tuning of the scanning time is not performed until data is once recoded to the test area so that the optimal scanning time is detected. Accordingly, in tuning the scanning time, the clear operation is not necessarily required although the entire test area is consumed. However, in order to perform the power calibration of the optical signal, the clear operation is necessarily required. That is, in order to tune the scanning time after the power calibration is performed by using the test area cleared, data is overwritten to the test area. Accordingly, the frequent data recording operations and clear operations may cause severe damages to the test area. As a result, the power level of the optical signal and scanning time cannot be properly compensated for. Thus, a data recording performance deteriorates.
Accordingly, there is a need for an improved optical recording/reproducing apparatus and method for rapidly and optically tuning a write strategy of an optical disk.